TABLE FOR MOLD EXTRACTION

Description

B0805IT INNOVA & PARTNERS Srl Patent description for industrial invention entitled: “Mold extraction table” Owner: Mengoni Michele -------------------- DESCRIPTION Field of invention The present invention relates to the field of injection molds. In particular, the This invention relates to a device for extracting a workpiece from an injection mold and an injection mold comprising said device of extraction. State of the art. The mold is a piece of equipment that allows you to give a certain shape to a piece of material to work or more half-shells or half-shapes, which go to to delimit an area of ​​space with the shape of the piece to be obtained. The mold is specially designed according to the transformation process used, such as, for example example, injection, die casting, deep drawing, foaming. Depending on the different type of processing, the characteristics and technology change of the mold. The molds are strictly tied to the type of material for which they will be used. used, on whose viscosity, temperature and characteristics numerous variables depend. mold is a piece of equipment that only works if inserted inside a machine, called “press”. Injection molding is an industrial manufacturing process in which a material plastic is melted and injected at high pressure into a closed mold, which It is opened after the artifact has solidified. B0805IT INNOVA & PARTNERS Srl The injection molding cycle begins when the mold closes, followed by from the injection of a material, typically a polymer, into the mold cavity. once the cavity is filled, a certain pressure value is maintained to compensate for the volumetric variations of the material. Once the part is sufficiently cool, the mold is opened and the molded piece is extracted. Extraction is generally achieved by the vertical movement of a table extraction, which typically comprises two movable plates screwed together, called as upper table and lower table the coffee table is fixed to columns that act as a guide for the table itself and which are fixed to a bottom plate in this way The table can slide freely without falling. The plates are used to position and move the extractors that act directly on the printed piece, without them fall. Normally, the table is held in place by two or more columns cylindrical which in turn prevent the table from moving. There are also some spacer elements, or spacers, which perform the function of creating a space between the lower bottom plate and the punch, which contains the semi-form of the mold. This way, the table can move freely in that space during the setting phase. mold extraction. The ejectors push the molded piece out of the semi- form. In large molds (especially in the automotive sector), to ensure the flatness of the extraction table during the handling phase, normally used hydraulic cylinders (two or four cylinders depending on the size of the table extraction) with well-balanced oil circuits. The Applicant has found that in these situations it is necessary to perform numerous additional processes which, together with the purchase of the cylinders themselves, determine an increase in the cost of the mold. B0805IT INNOVA & PARTNERS Srl Therefore, the Applicant faced the technical problem of how to create a system that allows the extraction table to be lifted uniformly, without unbalances and, at the same time, without the need for further special devices that determine resulting in additional costs. Summary of the invention According to a first aspect, the present invention refers to a device for the extraction of a machined part from an injection mold such as that shown in claim 1. The Applicant of this application has in fact surprisingly found that the The above mentioned technical problem can be solved effectively and reliably by a device for extracting a workpiece from an injection mold, wherein said device comprises: - at least a first rack and a second rack fixed to a first part - at least a third rack and a fourth rack fixed to a second part stop of said injection mold and synchronized to each other, and synchronized with - an extraction table placed between said first stationary part and said second part mold stop, wherein said table comprises at least one movable element capable of to slide along the said first, second, third and fourth racks. In this way, the mechanical sliding of the moving element is facilitated table to ensure its flatness during the opening of an injection mold in fact, the synchronization between the first, second, third and fourth rack allows to allow the moving element of the table to rise uniformly, without imbalances. B0805IT INNOVA & PARTNERS Srl Furthermore, thanks to the presence of the racks, the device is allowed to This invention provides an effective injection mold extraction without the use of additional devices, resulting in a further reduction in mold costs. Finally, thanks to the presence of the racks, the mobile plate of the table is able to slide vertically along them, uniformly, without coming into direct contact with the stationary parts of the mold. This avoids any unpleasant friction between the table and the stationary parts of the mold during the opening of the mold itself. According to a preferred embodiment, the device of the present invention also includes: - at least one first toothed rod provided, at one of its first ends, of a first joint element for the transmission of motion placed in correspondence of said first rack, and provided, in correspondence of one of its second end, opposite to its said first end, of a second element of joint for the transmission of motion placed in correspondence with said second rack, wherein said first toothed rod is adapted to interact with said first and second rack so that the rotation of said first toothed rod allows the sliding of said at least one movable element of the table along said first and - at least one second toothed rod provided, at one of its first ends, of a third joint element for the transmission of motion placed in correspondence of said third rack, and provided, at its second end, opposite to its first end, of a fourth connecting element for the transmission of motion placed in correspondence with said fourth rack, in which said second toothed rod is designed to interact with said third and fourth racks in such a way that the rotation of said second toothed rod allows the sliding of said at least a movable element of the table along the third and fourth racks B0805IT INNOVA & PARTNERS Srl - a third toothed rod suitable for synchronising said first and second toothed rods with each other and therefore suitable for synchronising the said first, second, third and fourth racks with each other. In this way, thanks to the presence of the toothed rods connected to each other, it is further guaranteed the flatness of the table during the opening of the mold injection. In fact, the rotation of any of the first, second or third toothed rods, each connected to the others, it allows the mobile element of the table to rise in a uniform, without imbalances. According to a first preferred embodiment, said at least one movable element of the table used in the device of the present invention comprises a movable plate upper and a lower movable plate connected to each other and substantially shaped rectangular, to which the extractors are connected which act directly on the piece printed to be extracted. According to a second further preferred embodiment, said at least one movable element of the table used in the device of the present invention comprises: - a first skate placed in correspondence with said first joining element for the - a second skate placed in correspondence with said second joining element - a third skate placed in correspondence with said third joining element for the - a fourth skate placed in correspondence with said fourth joining element for the B0805IT INNOVA & PARTNERS Srl wherein said first, second, third, and fourth skates are capable of sliding in a manner synchronized along, respectively, the first, second, third and fourth racks in following the rotation of the said first, second, third and fourth elements respectively of joint for the transmission of motion. In this way, the presence of the four skates as moving elements of the table allows you to reduce the overall dimensions of the table and, at the same time, allows a smooth and further balanced sliding of the table during opening of the mold. According to a preferred embodiment, each of said first, second, third and fourth rack is provided with a groove along which they are able to slide, respectively, called first, second, third, and fourth skate. In this way, each of the said racks, in addition to facilitating the sliding of the skates along the racks themselves, it also acts as a guide for the skates themselves. Furthermore, thanks to this guidance system, it is not necessary to use the columns typically used in standard tables for opening the mold, thus reducing the overall dimensions and providing more space available on the device, while maintaining a good stability and balance of the extraction table, avoiding any imbalances. According to a preferred embodiment, said first, second, third, and fourth skates They are U-shaped. In this way, thanks to the U-shape of each skate, the two opposite longitudinal edges of the U-shape of the skate are designed to engage with the contours of said groove, which then acts as a guide for the skate. According to a preferred embodiment, said connecting elements for the The transmission of motion is achieved by bevel gears. B0805IT INNOVA & PARTNERS Srl In this way, the bevel gears allow for better engagement and relative transmission of motion between the toothed rods, the shoes and the racks. According to a preferred embodiment, the device of the present invention also comprises a first ball bearing, a second ball bearing, a third ball bearing, and a fourth ball bearing each placed at a corresponding table runner, especially at one edge longitudinal of the U-shape of the skate. In this way, the ball bearings allow for a beneficial engagement to avoid friction. unwanted. According to an alternative embodiment, bushings or other elements may be used similar devices in place of ball bearings. According to a preferred embodiment, the device of the present invention It also includes a first plate, a second plate, a third plate, and a fourth plate placed, respectively, on said first, second, third, and fourth skate. In this way, the first, second, third, and fourth ball bearings are locked, respectively, from said first, second, third, and fourth plate on, respectively, called first, second, third, and fourth skates, thus avoiding unwanted movements of the bearings. According to a preferred embodiment, said first and second racks are parallel to each other, called third and fourth racks are parallel to each other, and each of said first, second, third and fourth rack includes an alternation of depressions and of crests, and in which the teeth of each of said first and second gear wheels are of dimensions such as to cooperate with the said depressions and crests of the corresponding racks. B0805IT INNOVA & PARTNERS Srl According to a preferred embodiment, each of said first, second, third and fourth rack is provided with a slot arranged along the longitudinal direction of it. This allows the insertion of an oil or lubricant into the slot. obtained in the rack in it for lubrication of the rack itself. According to a preferred embodiment, the device of the present invention It also includes a plug for each corresponding rack. In this way, the racks are synchronized with each other. According to a preferred embodiment, said pins are all arranged at the same height h. In this way, the racks are calibrated thanks to the pin always positioned at the same height. According to a preferred embodiment, the device of the present invention It also comprises a plurality of holes made in each of said racks, in which each of these holes is suitable for the insertion of a corresponding pin into it. In this way, each pin can be inserted into the corresponding hole to be fixed. to the corresponding rack. According to a preferred embodiment, the device of the present invention It also comprises a plurality of screws suitable for fixing said racks to said fixed parts of the mold. According to a second aspect, the present invention relates to a mould injection as set forth in claim 10. The Applicant of this application has in fact surprisingly found that the The above mentioned technical problem can be solved effectively and reliably by B0805IT INNOVA & PARTNERS Srl an injection mold that includes a device for extracting a workpiece worked from said mold as described above with reference to the first aspect of the present invention. Further features and advantages of the present invention will become apparent. highlighted by examination of the following detailed description of embodiments preferred, but not exclusive, illustrated only for indicative and non-limiting purposes with the support of the attached drawings. In particular, in these drawings: - Fig. 1 shows a complete closed view of the moving part of a mold that comprises a device of the present invention for extracting a workpiece from said mold - - Fig. 3 shows the mold of Fig. 1 a - Fig. 4 shows a view of Fig. 3 which also illustrates a series of - Fig. 5 shows the mold of Fig. 3 with the second fixed part removed and the upper table to show some elements of the device of the present invention for the extraction of a worked piece from said mold - Fig. 6 shows the device of Fig. 5 in which the lower extraction table is raised to the fully extended position - Fig. 7 shows a detail of the device of the present invention for the extraction of a machined piece from a mold in Fig. 5 - Fig. 8 shows a further detail of the device of the present invention for the extraction of a machined piece from a mold in Fig. 5 B0805IT INNOVA & PARTNERS Srl - Fig. 9 shows the arrangement of a pin in a rack shown in device of Fig. 8 - Fig. 10 shows a second embodiment of a device of the present invention for the extraction of a worked piece from a mold - Fig. 11 shows the device of Fig. 10 with the second part removed stop - Fig. 12 shows the device of Fig. 11 - Fig. 13 shows a top view of the device in Fig. 12 - Fig. 14 shows the device of Fig. 12 with all parts removed - Fig. 15 shows a detail of a skate from Fig. 12 - Fig. 16 shows a further detail of the skate in Fig. 15 in which the - Fig. 17 shows a detail of a rack of the device of Fig. 10. Detailed description The following detailed description refers to particular embodiments of the device of the present invention for extracting a workpiece from a mold, without limiting its content. With reference to Fig. 1-9 and Fig. 10-17, a description is given, respectively, first and a second embodiment of such device. Fig. 1 shows a closed complete view of the moving part of a mold 1 containing a device of the present invention for extracting a workpiece from the mold 1. In particular, the fixed base plate 8 of the mold is visible, on the on which the movable plate 22 of the lower table rests, to which the plate is screwed B0805IT INNOVA & PARTNERS Srl furniture 10 of the upper table. Also visible are the columns 23, positioned between the movable plate 22 of the lower table and the movable plate 10 of the upper table. It is also visible is the empty space 25 between the fixed base plate 8 and the punch 17 which contains the semi-form of the mold. In this way, the movable plate 10 of the table upper can move freely in this space 25 during the extraction phase of the die. Fig. 2 shows an exploded view of the mold of Fig. 1 in order to show more in detail a first part stops 6 and a second part stops 7, parallel to the first part stops 6, which act as spacers between the fixed base plate 8 and the punch 17 and between the where the coffee table is positioned. Fig.3 shows some elements of the device 1 of the present invention are more visible, including a first rack 2a and a second rack 2b, parallel to each other, fixed to the first stationary part 6 of the extraction device 1 and suitable for engaging with the movable plate 10 of the upper table to allow it to be lifted. Fig. 4 shows a view of Fig. 3 which also shows a series of extractors 21 which serve to eject the worked piece from the mold 1. Fig. 5 shows the device of Fig. 3 with the second stationary part 7 removed. and the movable plate 10 of the upper table, and in which a first rod is also visible 3rd toothed connected, at its opposite ends, respectively to the first rack 2a and to the second rack 2b. In this way, the first rack 2a and the second rack 2b are synchronized to each other. Furthermore, it is shown a second toothed rod 3b, arranged along the second stationary part 7 (not visible in Fig. 5 because removed to show the details), parallel to the first toothed rod 3rd and intended to coordinate between them a third rack and a fourth rack fixed to the second part stops 7, in a similar way to what was seen above in relation to the B0805IT INNOVA & PARTNERS Srl arrangement of the first rack 2a and the second rack 2b connected between them by means of the first toothed rod 3a (in Fig. 3 the presence of the third and fourth rack is easily understood, even if not actually shown, as it was removed the second fixed part 7 to which the third and fourth racks are fixed). also shown a third toothed rod 3c, arranged perpendicular to the first rod toothed 3a and the second toothed rod 2b, and suitable for synchronising them together first toothed rod 3a and second toothed rod 2b. Fig. 6 shows the movable plate 22 of the lower table in its maximum extension. away from the fixed base plate 8 of the mold in order to facilitate extraction from the mold of the worked piece. Also in Fig. 6, as in Fig. 5 described above, the second fixed part 7 and the movable plate 10 of the upper table have been removed for show some details of device 1 that are otherwise not visible. They are also visible the safety extractors 26, typically also present in the molds known in the art (in addition to the typical extractors 21 shown in Fig. 4) and placed one in correspondence of each of the four corners of the movable plate 22 of the lower table. Figs. 7 and 8 show details of Figs. 5 and 6, highlighting how the third rod toothed 3c fits into the first toothed rod 3a and like the latter it connects to the rack 2a via gear wheel 4a. Fig. 8 also shows a pin 5a pair of such pins 5a,5b are shown in Fig. 9, respectively inserted in rack 2a and rack 2b, both arranged at the same height / depth h so as to calibrate the racks 2a,2b uniformly. Fig. 9 also shows a plurality of screws 24 suitable for fixing the rack 2a. to the fixed part 6 of the mold. With this embodiment, thanks to the presence of the racks 2a,2b,2c,2d connected to each other, mechanical sliding is facilitated in a uniform manner, without B0805IT INNOVA & PARTNERS Srl imbalances. of the moving element of the table to ensure its planarity during the opening of the injection mold. Finally, thanks to the presence of the racks 2a,2b,2c,2d, the mobile plate of the table it is able to slide along them, without coming into direct contact with the stationary parts 6,7 of the mold. This way, any unpleasant friction between the table and the parts is avoided. 6,7 stops of the mold during the opening of the mold itself. Figs. 10-17 show a second embodiment of the present invention which It differs from the first embodiment shown above with reference to Fig. from 1 to 9 due to the fact that the upper table 10 includes a first, second, third, and fourth skate 10a,10b,10c,10d, placed in correspondence, respectively, with the first, second, third and fourth racks 2a,2b,2c,2d, as best shown in Fig. 12 to 14. In particular, Fig. 10 shows a device 1 of the present invention which comprises: a) a first stationary part 6 of the injection mould on which the first rack 2a and the second rack 2b, b) a second stationary part 7 of the injection mold, parallel to the first stationary part 6, c) a movable plate 10 of the upper table for extracting a machined piece from the mold, placed between the first fixed part 6 and second fixed part 7 of the mold, and) a fixed base plate 8 of the mold on which the movable plate 22 of the lower table rests before the its lifting. Furthermore, unlike the embodiment shown in Fig. 3, Fig. 10 also shows the guides 9a,9b placed in correspondence, respectively, of the first and second rack 2a,2b respectively, the first and second skate 10a,10b (as shown in detail in the Fig. 12). Fig. 11 shows the device of Fig. 10 with the second stationary part 7 removed. the third rack 2c and the fourth rack 2d are also shown, with the B0805IT INNOVA & PARTNERS Srl respective guides 9c,9d on which the third and fourth are inserted respectively skate 10c,10d (as shown in Fig. 13 and 14). Fig. 12 shows the device of Fig. 11 with the movable plate 10 also removed. of the upper table. In Fig. 12 the following are also visible: a) the first toothed rod 3a which connects the first rack 2a and the second rack 2b, b) the second toothed rod 3b which connects the third rack 2c and the fourth rack 2d, and c) the third toothed rod 3c, which connects the first toothed rod 3a and the second rod toothed 3b. In Fig. 12 the first and second fixed skates 10a,10b are also visible, respectively, on the guides 9a,9b and the third and fourth skates 10c,10d. Fig. 13 is a top view of the device of Fig. 12 clearly showing the four skates 10a,10b,10c,10d corresponding to the four racks 2a,2b,2c,2d, connected to each other by the three toothed rods 3a,3b,3c. Fig. 14 shows the device of Fig. 12 with all fixed parts removed. furthermore showcasing the four skates 10a,10b,10c,10d in correspondence with the four racks 2a,2b,2c,2d, connected to each other by the three toothed rods 3a,3b,3c. Fig. 15 shows a detail of the skate 10a 2 longitudinal sides of the U of the skate 10a are arranged around the gear wheel 4a and they slide using the groove 20 obtained in the lower part of the rack 2a. Similarly, although not shown in detail in the figures, the second, third and fourth skate 10b,10c,10d have the same shape and are arranged in the same way as the skate 10a shown in detail in Fig. 15. Fig. 16 shows a further detail of the U-shaped skate 10a which is fixed on the , after it has been inserted into the appropriate seat of the 10a skate, to engage with the skate B0805IT INNOVA & PARTNERS Srl same 10a. In addition, to avoid unwanted movements, there is a 12a plate which has the function of locking the ball bearing 11a on the skate 10a. Fig. 17 shows a detail of a rack 2a of the device of Fig. 10, although the same considerations can be applied in a similar way to the second one, third and fourth rack 2b,2c,2d. In each rack there is an alternation of depressions 13 and crests 14, so that the teeth 15 of each of said gear wheels conics 4a,4b,4c,4c (shown in Fig. 16) can cooperate with the corresponding depressions 13 and crests 14 of racks 2a,2b,2c,2d. Furthermore, each rack 2a,2b,2c,2d is provided with a slot 16 in which it is possible add oil or lubricant to lubricate the rack itself. In the rack 2a of Fig. 17 a seat for inserting the pin 5a is also visible. As will be noted, in the embodiments shown with reference to Figs. 10-17 there are no there is no column, typically present in the molds known in the art. In fact, thanks in the presence of the skates 10a,10b,10c,10d in the embodiment shown with referring to Fig. 10-17, the presence of columns is no longer necessary, since the their function is to avoid unwanted movements during the extraction of the mold performed by skates 10a,10b,10c,10d. Therefore, with this embodiment, since the columns are not necessary, we obtain a cost saving and a smaller footprint on the extraction table. Of course, many changes and variations will be evident to people who are familiar with the field. of the preferred embodiments described above, still remaining within of the scope of the invention. Therefore, the present invention is not limited to the preferred embodiments. described, illustrated for illustrative and non-limiting purposes only, but is defined by the claims that follow.

Claims

Claims.

1. Device for extracting a machined part from an injection mold (1), wherein said device comprises: - a first rack (2a) and a second rack (2b) fixed to a first stationary part (6) of said injection mold (1) and synchronized with each other; - a third rack (2c) and a fourth rack (2d) fixed to a second stationary part (7) of said injection mold (1) and synchronized with each other, and synchronized with said first rack (2a) and second rack (2b); and - an extraction table interposed between said first stationary part (6) and said second stationary part (7) of the injection mold (1), wherein said extraction table comprises at least one movable element (10) capable of sliding along said first, second, third and fourth rack (2a,2b,2c,2d).

2. Device according to claim 1, further comprising: - at least one first toothed rod (3a) provided, at a first end thereof, with a first joint element (4a) for the transmission of motion placed at said first rack (2a), and provided, at a second end thereof, opposite to said first end thereof, with a second joint element (4b) for the transmission of motion placed at said second rack (2b), wherein said first toothed rod (3a) is adapted to interact with said first and second racks (2a,2b) so that the rotation of said first toothed rod (3a) allows the sliding of said at least one movable element (10) of the extraction table along said first and second racks (2a,2b); - at least a second toothed rod (3b) provided, at one of its first ends, with a third connecting element (4c) for the transmission of motion B0805IT INNOVA & PARTNERS S.rl placed in correspondence with said third rack (2c), and provided, in correspondence with its second end, opposite to said first end, with a fourth joint element (4d) for the transmission of motion placed in correspondence with said fourth rack (2d), in which said second toothed rod (3b) is able to interact with said third and fourth racks (2c,2d) so that the rotation of said second toothed rod (3b) allows the sliding of said at least one mobile element (10) of the extraction table along said third and fourth racks (2c,2d); and - a third toothed rod (3c) able to synchronise said first and second toothed rod (3a,3b) with each other and therefore able to synchronise said first, second, third and fourth racks (2a,2b,2c,2d).

3. Device according to claim 1 or 2, wherein said movable element (10) of the extraction table comprises: - a first shoe (10a) placed in correspondence with said first joint element (4a) for the transmission of motion; - a second shoe (10b) placed in correspondence with said second joint element (4b) for the transmission of motion; - a third shoe (10c) placed in correspondence with said third joint element (4c) for the transmission of motion; - a fourth shoe (10d) placed in correspondence with said fourth joint element (4d) for the transmission of motion; - wherein said first, second, third, and fourth shoe (10a,10b,10c,10d) are capable of sliding in a synchronized manner along, respectively, said first, second, third, and fourth rack (2a,2b,2c,2d) following the rotation, B0805IT INNOVA & PARTNERS Srl respectively, of said first, second, third, and fourth joint element (4a,4b,4c,4d) for the transmission of motion.

4. Device according to claim 3, wherein each of said first, second, third and fourth racks (2a,2b,2c,2d) is provided with a groove (20) along which said first, second, third and fourth shoes (10a,10b,10c,10d) are able to slide, respectively.

5. Device according to claim 4, wherein said first, second, third, and fourth skates (10a,10b,10c,10d) are U-shaped, and wherein the two opposite longitudinal edges of the U are adapted to engage with said groove (20).

6. A device according to any of claims 3 to 5, further comprising a first ball bearing (11a), a second ball bearing (11b), a third ball bearing (11c), and a fourth ball bearing (11d) located at said first, second, third, and fourth pads (10a,10b,10c,10d).

7. The device of claim 6, further comprising a first plate (12a), a second plate (12b), a third plate (12c), and a fourth plate (12d) arranged to lock said first, second, third, and fourth ball bearings (11a,11b,11c,11d) onto, respectively, said first, second, third, and fourth pads (10a,10b,10c,10d).

8. Device according to any of the preceding claims, wherein said connecting elements (4a,4b,4c,4d) for transmitting motion are bevel gear wheels (4a,4b,4c,4d).

9. Device according to any of the preceding claims, further comprising a pin (5a,5b,5c,5d) for each corresponding rack (2a,2b,2c,2d).

10. Injection mould (1) comprising a device for extracting a machined piece according to any of claims 1 to 9.